This study is a cluster-randomized controlled trial of a peer-led multilevel and multi-component HIV intervention among women at high risk. The main objectives are: (1) to design and implement an HIV intervention that combines individual cognitive and social influence approaches with peer education;(2) to evaluate the efficacy of such behavior intervention;and (3) to identify important mediating or moderating factors of HIV risk behavior and behavior change. With 840,000 people estimated to be infected with HIV by 2003, concerted efforts are needed to fight the AIDS epidemic in China. The danger that the epidemic can make a quick inroad to the general population through sexual transmission underscores the urgent need for more effective and sustainable HIV intervention among the target population, who are at high risk of acquiring HIV and a critical source of sexual transmission of HIV. However, few interventions have targeted women at high risk of HIV in China. The central hypothesis of the study is that, given the marginal socioeconomic status of the target population, HIV information is necessary but not sufficient for behavior change;they need to be motivated to take protective actions, be confident that they have the ability and skills to manage difficult situations, and in a social and working environment empowering of HIV behavior change. HIV intervention will be most effective if delivered in small group sessions by peers and attending to both cognitive and social processes of behavior change and cultural and gender appropriateness. This conceptualization of effective HIV behavior change will be tested and evaluated among about 712 women working in the entertainment industry. Participants will be selected through cluster-randomization sampling, in which the clusters are the entertainment establishments. All eligible women from the sampled establishments will be recruited and assigned with equal numbers to either an intervention or a control condition. Both groups will receive standard voluntary counseling and testing (VCT). But the intervention group will receive additional motivation enhancing and gender-specific empowerment skills trainings delivered by trained peer educators, augmented by peer outreach and a structural intervention component among owners of establishments to promote enabling social, normative, and working environments supportive of HIV risk reduction. The efficacy of the intervention will be evaluated through assessment of self-reported HIV risk and preventive behaviors and newly detected STIs at 3-, 6-, and 12-month post intervention between the intervention and the control groups. Findings will have far reaching implications for effective HIV prevention intervention among women at high risk in China. China's success will in turn be a key to global success in preventing the spread of HIV.